Electric conduit.



WWNESSES N. W. BUGH.

ELECTRIC GONDUIT.

AYILIGATION FILED JAN. 29, 1912.

Patented Mar. 3, 1914.

INVENTOR UNITED STATES PATENT OFFICE.

NEWTON W. BUGH, OF NEW CASTLE, PENNSYLVANIA, ASSIGNOR TO SAFETY ARMOBITE CONDUIT COMPANY, OF PITTSBURGH, PENNSYLVANIA, A CORPORA- TION OF PENNSYLVANIA.

ELECTRIC CONDUI'I.

Specification of Letters Patent.

Patented. Mar. 3, 1914.

To all whom it may concern Be it known that I, NEWTON WV. Boon, a resident of New Castle, in the county of Lawrence and State of Pennsylvania, have invented a new and useful Improvement in Electric Conduits, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, forming part of this specification, in which the figure is a longitudinal section of conduit made in accordance with my invention.

My invention relates to the class of rigid metallic conduit, provided with protective coatings, and is designed to provide an improved and more effective conduit of this character.

To that end, the invention consists in a pipe having an interior coat of flexible enamel superimposed on a coat of oil paint. The paint may be applied directly to the interior surface of the pipe or to a metallic coating, first applied thereon, such coating being preferably in the form of zinc applied either by electrogalvanizing or sherardizing.

The invention further consists in such a pipe having an exterior coating of zinc with a superimposed coating of oil paint thereon.

In carrying out my invention in its preferred form, I first apply a Zinc coating 8 to the outer, and preferably to both the inner and outer surfaces of the pipe 2, this zinc coating being applied either by electro-deposition or sherardizing, that is a cold or dry process, as distinguished from the ordinary hot galvanizing process; or by any process depositing a smooth coating of Zinc. This galvanized pipe is then painted inside and out with an oil paint 4: preferably consisting of oxid of iron ground in oil (such as linseed or soja oil, or a mixture of the two) with shellac or gums added to keep the oxid in suspension. This coating as used by me is ordinarily of a red color from the natural color of the oxid of iron. This coating is found to be tenacious and not to crack under bending. This paint is also highly resistant to corrosion and is also found to possess insulating properties to some extent. To the interior of the pipe, I then apply a coating of smooth flexible enamel 5, which gives a smooth surface for the interior through which the wires may be fished. This enamel may be composed of ordinary black varnish mixed with a suitable solvent, such as ben Zin. This enamel coating is superimposed on the paint coating applied to the interior.

The advantages of my invention result from the use of the oil paint, to which the flexible enamel is applied, and also from the external coat of paint applied over the cold galvanizing. The internal paint coating aids in preventing corrosion and appears to assist in giving good adhesion between the enamel coating and the metal. The external paint coating aids in preventing corrosion, and both coatings help to give insulating qualities.

Variations may be made in the kind of paint used, in the enamel composition, the method of applying the metallic coating, etc, without departing from my invention.

I claim:

1. As a new article of manufacture, a metal pipe having its interior provided with a coating of oil paint, and a coating of flexible enamel superimposed upon said paint layer, substantially as described.

2. As a new article of manufacture, a metal pipe having an interior layer of oil paint, and a layer of flexible enamel superimposed thereon, said pipe having a thin,

uniform coating of zinc, substantially as described.

In testimony whereof, I have hereunto set my hand.

NEWTON IV. BUCH.

WVitnesses JAMns Knox, WV. L. BROADBENT.

Copies of this patent may be obtained for five cents each, by addressing the flommissioner of Patents.

Washington, D. C. 

